Optical properties of a hexagonal C/BN framework with sp2 and sp3 hybridized bonds.
Sci Rep
; 10(1): 6808, 2020 Apr 22.
Article
em En
| MEDLINE
| ID: mdl-32321931
ABSTRACT
We investigated the optical properties and roles of sp2- and sp3-hybridized bonds of a hexagonal C/BN family using first-principles calculations. The calculated phonon dispersions confirm the dynamic stability of Hex-(BN)6C12 and Hex-C12(BN)6. The complex dielectric function evolves from the infrared to the ultraviolet region and has a significant anisotropy for different polarizations. The reflectivity and refractive index spectra show that the sp2-hybridized C atoms are more sensitive to the light from infrared to visible region than B-N pairs while the C atoms and B-N pairs have a similar sensitivity to high frequencies. The sharp peaks of the energy-loss spectrum are all concentrated in the 23-30 eV energy region, which can be used to identify these hexagonal structures. The calculated band structures show Hex-C24 and Hex-(BN)6C12 are metals, but Hex-C12(BN)6 and Hex-(BN)12 are semiconductors with indirect band gaps of 3.47 and 3.25 eV, respectively. The electronic states near the Fermi level primarily originate from sp2-hybridized atoms. In addition, sp2-hybridized bonds are the main elements affecting the optical and electronic structure of C/BN materials with sp2- and sp3-hybridizations. We expect that the results presented will help understand the optical properties of C/BN materials containing sp2- and sp3-hybridized C atoms and B-N pairs.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Sci Rep
Ano de publicação:
2020
Tipo de documento:
Article